My Method
Made two saw horses from 2"x6" and padded top with cheap carpet.
Buy one sheet of 3/4"x4'x8' high quality plywood
Buy four car jacks
Buy 2"x4" stud quality boards to be cut for stacking support blocks
Put the horses near the ends of the 8' length of the plywood under the fuselage. Put the jacks near the four corners of the plywood and jack this fuselage support structure to the desired height. Stack 2x4s under the plywood to stabilize the load. After inserting the wing with bolts through the MLG mounts, the spar and the fuselage structure (MUCH easier said than done on and RV-6A) the jacks and support structure are also useful for for getting the fuselage reference plane exactly level (fwd & aft and side to side) for setting the wing incidence angle before drilling the mounting holes in the rear spar and fuselage fittings (do not assume the wings are at the correct fwd & aft angle with respect to the fuselage when you have the 60+ bolts in the main spar attachment location - on mine, one was OK but the other required significant twist to achieve the correct incidence angle - the airplane flies great by the way, ~380 hrs).
I can't insert photos anymore so I hope the description works for you.
Bob Axsom